As an imitation of the biological nervous systems, neural networks, which have been characterized as powerful learning tools, are employed in a wide range of applications, such as control of complex nonlinear systems, optimization, system identification, and patterns recognition. This article aims to bring a brief review of the state-of-the-art NNs for the complex nonlinear systems by summarizing recent progress of NNs in both theory and practical applications. Specifically, this survey also reviews a number of NN based robot control algorithms, (...) including NN based manipulator control, NN based human-robot interaction, and NN based cognitive control. (shrink)

ABSTRACT Academic dishonesty has remained high in Chinese college students. We examined Chinese college senior students’ everyday academic practices, especially academic dishonesty, considering the contextual changes inside and outside higher learning settings in China. Data were collected from 120 college seniors from four universities and were analyzed using a qualitative content-based exploratory approach in NVivo 10. Three themes were identified, including college seniors’ perceptions of academic dishonesty, contextual influences on academic dishonesty, and seniors’ personal attitudes about academic misconduct. Interview results (...) indicated that the contextual changes have reduced cheating both at the national level and at the college level; however, some contextual factors stubbornly remain unchanged, suggesting that the current, contextual climate on and beyond the Chinese college campuses should be restructured, not necessarily exclusively using top-down approaches. A theoretical model was provided to illustrate mechanisms associated with these students’ academic misconduct. Suggestions are discussed regarding future research and implications made for university personnel practice. (shrink)

Facial muscle activities are essential for the appearance and communication of human beings. Therefore, exploring the activation patterns of facial muscles can help understand facial neuromuscular disorders such as Bell’s palsy. Given the irregular shape of the facial muscles as well as their different locations, it should be difficult to detect the activities of whole facial muscles with a few electrodes. In this study, a high-density surface electromyogram system with 90 electrodes was used to record EMG signals of facial muscles (...) in both healthy and Bell’s palsy subjects when they did different facial movements. The electrodes were arranged in rectangular arrays covering the forehead and cheek regions of the face. The muscle activation patterns were shown on maps, which were constructed from the Root Mean Square values of all the 90-channel EMG recordings. The experimental results showed that the activation patterns of facial muscles were distinct during doing different facial movements and the activated muscle regions could be clearly observed. Moreover, two features of the activation patterns, 2D correlation coefficient and Centre of Gravity were extracted to quantify the spatial symmetry and the location of activated muscle regions respectively. Furthermore, the deviation of activated muscle regions on the paralyzed side of a face compared to the healthy side was quantified by calculating the distance between two sides of CGs. The results revealed that corr2 of the activated facial muscle region in Bell’s palsy subjects was significantly lower than that in healthy subjects, while CG distance of activated facial region in Bell’s palsy subjects was significantly higher than that in healthy subjects. The correlation between corr2 of these regions and Bell’s palsy [assessed by the Facial Nerve Grading Scale 2.0] was also significant in Bell’s palsy subjects. The spatial information on activated muscle regions may be useful in the diagnosis and treatment of Bell’s palsy in the future. (shrink)

. A new spatial-frequency image enhancement algorithm via wavelet homomorphic filtering transform is proposed to enhance the contrast of an image. The wavelet analysis coefficients are processed using a high-pass filter to amplify the high spatial frequencies and attenuate the low spatial frequencies. So the object features can be emphasized while the undesired contributions within the image due to light source nonuniformity can be reduced. Experimental results show that this new algorithm can gain better performance in enhancing the local contrast (...) of an image while maintaining its global appearance, in contrast to some representative algorithms. (shrink)

In this paper, an adaptive sliding mode control method based on neural networks is presented for a class of manipulator systems. The main characteristic of the discussed system is that the output variable is required to keep within a constraint set. In order to ensure that the system output meets the time-varying constraint condition, the asymmetric barrier Lyapunov function is selected in the design process. According to Lyapunov stability theory, the stability of the closed-loop system is analyzed. It is demonstrated (...) that all signals in the resulted system are bounded, the tracking error converges to a small compact set, and the system output limits in its constrained set. Finally, the simulation example is used to show the effectiveness of the presented control strategy. (shrink)

A new medical image enhancement algorithm based on spatial frequency domain is presented in this article. The medical image is first divided into several sub-images based on dyadic wavelet scale analysis. At each level, different directional sub-band images can reflect the different characteristics of the image. A low-frequency sub-band image maintains the original image content information, and high-frequency sub-band images represent image details such as edges and regional boundaries. The corresponding sub-band images are then enhanced by different Butterworth homomorphic filtering (...) functions, which can attenuate the low frequencies and amplify the high frequencies. A linear adjustment is carried out on the low frequency of the highest level. Then, the wavelet reconstruction course is used to obtain the final enhanced image. Experiments on magnetic resonance images of temporomandibular joint soft tissues have shown that the proposed method can effectively eliminate the non-uniform luminance distribution of medical images. Its performance is much better than traditional Butterworth homomorphic filtering algorithm whether in subjective vision quality or objective evaluations such as detailed information entropy and average gradient. (shrink)

The revolution has not yet succeeded. Comrades, carry on! On February 17, 1904, one month after the Russo-Japanese War broke out in northeastern China (Manchuria), Cai Yuanpei,1 a prominent Chinese intellectual, began to publish his short story “Xinnian meng” (New Year’s dream) in Eshi jingwen (Alarming news about Russia), a daily based in Shanghai.2 In this piece, Cai depicts his dream of a future world where humans ultimately achieve universal freedom and affluence. The contemporary scholar Arif Dirlik praised Cai Yuanpei’s (...) creativity, regarding “New Year’s Dream” as worthy of inclusion in an “anarchist canon.”3 Cai Yuanpei, although a prestigious scholar and educator and the most famous chancellor of .. (shrink)

An improved image enhancement approach via nonsubsampled contourlet transform is proposed in this article. We constructed a geometric image transform by combining nonsubsampled directional filter banks and a nonlinear mapping function. Here, the NSCT of the input image is first decomposed for L-levels and its noise standard deviation is estimated. It is followed by calculating the noise variance and threshold calculation, and computing the magnitude of the corresponding coefficients in all directional subbands. Then, the nonlinear mapping function is used to (...) modify the NSCT coefficients for each directional subband, which keeps the coefficients of strong edges, amplifies the coefficients of weak edges, and zeros the noise coefficients. Finally, the enhanced image is reconstructed from the modified NSCT coefficients. Three experiments are carried out respectively on images from subjective vision quality and objective evaluation measures. The first experiment is the algorithm performed on images. The subsequent experiments are the information entropy and spatial frequency. The experimental results demonstrate that the proposed method can gain better performance in enhancing the low-contrast parts of an image while keeping its clear edges. (shrink)

It could be claimed that without any doubt the Internet has revolutionized the educational system to a great extent. Even though some are still interested in traditional ways of teaching and learning and also face-to-face classes, technological advances, in particular, social media have changed the English as a foreign language contexts in a way that they will not be compatible with any other methods that have long been utilized before. Despite the fact that some studies have been conducted in different (...) learning contexts, to the researcher’s best knowledge, attention has not been focused on the importance of social media inside and outside the classroom on EFL students’ indulgence. Therefore, the aim of this review is to synthesize the findings of the previous studies to highlight the role of social media in EFL students’ engagement throughout class and outside the class in both face-to-face and online classes. To reach this goal, this review first discusses the impact of social media on engagement, and then engagement and its classifications are dealt with. Next, the relationship between using social media and students’ engagement is discussed. And finally, some implications are proposed. (shrink)

Wearing a myoelectric prosthesis is a basic way for limb amputees to restore their lost limb functions in the activities of daily living. However, it is estimated that around 40% of amputees refuse the prosthesis. One of the primary reasons would be that the current prostheses lack appropriate sensory feedback. Currently, the amputees only depend on their visual feedback when using their arm prostheses. It would be difficult for them to accurately control the wrist position, which is vital for flexible (...) manipulation in ADLs. This manuscript designed a myoelectric arm prosthesis with wrist position feedback. To study the effect level of position feedback on prosthetic control, two tests were performed. The vibrotactile perception range test aims to analyze the perception sensitivity of the vibration in humans and obtain the optimal perception range utilized in the sensory feedback test. The sensory feedback test analyzes the effectiveness of the position feedback by comparing three feedback methods of Vis-FB, WP-FB, and a combination of Vis-FB and WP-FB. These tests were conducted by asking six able-bodied subjects to perform 20 movement combinations of five target positions. The WP-FB was transiently activated with five vibrating motors embedded in an armband to stimulate the arm stump when the prosthetic wrist rotates to the target positions. Our experimental results showed that when WP-FB was added to the prosthetic control, the absolute angular error of the prosthetic wrist declined from 4.50° to 1.08° while the success rate 3 increased from 0.34 to 0.84, respectively. This study demonstrates the importance of WP-FB to the effective control of the arm prosthesis. (shrink)

ABSTRACT This essay is motivated by the seeming contradiction that Korean unification is sought after by most Koreans yet speculations about the social and cultural changes it might bring are almost absent. This may be because Korean unification denotes a series of differences contrasted to the present—because it is a potent “master symbol” with one foot in utopian speculation and the other in policy studies. In this essay, I outline some of the complexities, starting with an examination of illustrations of (...) unification in textbooks for the tensions and contradictions they introduce. I then turn to fiction and film, sketching not only what some South Koreans hope will happen after unification with the North but, indeed, the limits of their imagination regarding what the future will hold for South Korea. In the end, I concur with Grinker that representations of unification are “utopian,” but I object to the association of “utopia” with a socially engineered straitjacket. On the contrary, the utopias projected here suggest stepping off a precipice into worlds unknown, futures defined by their radical difference from today. The end of the essay locates these more imaginative dimensions of Korean unification in the “hope” of Ernst Bloch. (shrink)